CVE-2025-59284 — Windows NTLM Spoofing Vulnerability

Executive Summary

Exposure of sensitive information to an unauthorized actor in Windows NTLM allows an unauthorized attacker to perform spoofing locally.

Overview

5.5

CVSS MEDIUM

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Spoofing

Weakness CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

Released Oct 14 2025

Last Updated Oct 14 2025

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.00965 — 0.58638 percentile

NVD CVSS 5.5 MEDIUM — differs from MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

None

USER INTERACTION

Required

SCOPE

Unchanged

CONFIDENTIALITY

Low

INTEGRITY

None

AVAILABILITY

None

EXPLOIT CODE MATURITY

Unproven

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 2.9

EPSS Score

0.00965

probability of exploitation in the next 30 days

0.58638 percentile - updated 2026-08-14

View on FIRST.org

Affected Products

10 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 11 Version 22H2 for ARM64-based Systems	`5066793 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 22H2 for x64-based Systems	`5066793 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 23H2 for ARM64-based Systems	`5066793 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 23H2 for x64-based Systems	`5066793 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 24H2 for ARM64-based Systems	`5066835 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 24H2 for x64-based Systems	`5066835 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 25H2 for ARM64-based Systems	`5066835 (Security Update)`	Important	Spoofing	Yes
Windows 11 Version 25H2 for x64-based Systems	`5066835 (Security Update)`	Important	Spoofing	Yes
Windows Server 2025	`5066835 (Security Update)`	Important	Spoofing	Yes
Windows Server 2025 (Server Core installation)	`5066835 (Security Update)`	Important	Spoofing	Yes

Patches

2 patches

Article	Type	Restart
`5066793`	Security Update	Yes
`5066835`	Security Update	Yes

Exploits & PoC

1 public PoC

Unverified third-party code

Public proof-of-concept repositories aggregated from PoC-in-GitHub. They are not reviewed and may be incomplete, non-functional, or malicious — inspect the code before running anything.

Repository	Stars	Published	Description
lytnc/CVE-2025-59284-PoC	5	2026-03-13	Proof of concept for CVE-2025-59284 libarchive exploit

Detection Rules

No public Sigma or Nuclei detection rule has been mapped to this CVE yet. Coverage is concentrated on exploited / high-profile vulnerabilities; check SigmaHQ for updates.

Acknowledgments

Len Sadowski and Oguz Bektas working with Trend Zero Day initiative

References

MSRC Advisory MITRE NVD